Fig. 6

Kaplan–Meier survival curve of progression-free survival (RFS) stratified by the combined model. Survival risk stratification of the combined model was measured by Kaplan–Meier analysis and the p value was calculated using log-rank test according to risk scores grouped by the optimal cutoff. The result showed the nomogram had significant capability to risk stratification (p < 0.05), both in the training set (a) and the validation set (b). The red line was the patients with predicted microsatellite instability high (pred-MSI-H), and the blue line showed the patients with predicted microsatellite instability low or microsatellite stable (pred-MSI-L/MSS)